Automatic presser-foot mechanism



Patented Sept. 8, 1925.

vUNITED ls'rxrns 1,553,073 PATENT OFFICE.

LEO J. DU MAIs AND FLOYD E. MINER, OR CHICAGO, ILLINOIS, AssIGNORs To CHICAGO SHOE MACHINERY COMPANY, or CHICAGO, ILLINOIS,- A CORPORATION OF ILLINOIS.

AUTOMATIC PRESSER-.FOOT MECHANI'SM.

Applicationl'ed 0ctober..8\,v1923. Serial No. 666,236,

To all 'whom t may concern.'-

Be a known that We, LEOJ. DU Mamma- FLoYD E. MINER, citizens -of the United.

IStates, and residents of Chicago, in the county of Cook and State of Illinois, have invented certain new and usefulImprovements in Automatic Presser-Foot Mechanism, of which the following is a specification. f

This invention relates, generally, to improvements'in sewing machines, and,l more particularly to leather stitching or sewing machines of the type which'employ an oscil- 1`- latory curved awl for piercing and feeding particularly to an automatic the work and an oscillatory curved needle having a notch near its free end for engaging the thread, said awl and needle operating from opposite sides of the work, but presser-foot mechanism therefor. f l

The principal Object of theinvention, is the pro-vision of a novel and improved mechanism `for actuating and locking the f presser-foot intermittently, by means of which mechanism the presser-foot vis operated' for clamping and automatically and positively locking the work on the worksupport of the machine during thegreater portion of a cycle, or during the stitch forming operation, and for releasing it from' the vwork during the lesser portion of thek cycle, or during the work-feeding movement of the awl. v r

Other objects of the invention, vare, to provide yielding means to hold the presserfoot in engagement with the work in such a way as to permit it to accommodate itself to different' thickness of the work and man' ually operable means for releasing said locking means and raising the presser-foot at any time during the cycle', whereby the work may be inserted, adjusted or withdrawn.

' Numerous other objects and' advantages of the invention will become apparent from the following description and explanation.

The invention consists in the parts and in the arrangement and combinations of parts hereinafter described and claimed.

In the accompanying drawings, which serve Vto illustrate an embodiment of the invention, and in which corresponding numerals of reference refer to like parts throughout the dierent views thereof,-

Fig. 1 is a view in side elevation of a" portion of the supportingframe of a leather stitching machine showing thev mechanism mounted thereon and only the partsof the machine which are directly associated with the present invention. Y Y

Fig. 2 is a front face view `of the parts in the same relation to one another as shown in Fig. 1. v Y l Fig. 3 is a view somewhat similar to Fig.

- 1 showing parts of the supporting frame of the machine, a part of the cam which operates the mechanism illustrating the locking mechanism for the presser-foot, a portion of which has been broken away to disclose saidlocking mechanism. In this view the parts are shown inthe positions they will assume just prior to the locking engagement ofthe presser-footwith the work.

Fig.v 4 is a detached perspective view of the upper portion ofthe locking lever of the device, and

4Fig. 5 is a detached perspective view of the trigger or releasing member for the jaw of the' locking lever;v

Referring tothe drawings, the reference numeral 6 designates a portion of one of the uprights on which the main or drive shaft 7 ofthe machinev isv transversely and horizontally mounted rearwardly of the uprights orstandards 8 at thefront portion of the machine, which standards are spaced apart laterally and carry at their upper portions a horizontally disposed shaft 9 upon which shaft the needle and awl of the machine .is mounted for oscillatory movement onv opposite vsides of the work support, the said shaft being mounted fory longitudinally slidable movement or reciprocation so as to afordlateral movement to the awl, all

of which is well known to those skilled in the art, and for this reason it has been' ypresser-foot comprises a bar or member 11 having at its upper'end a lateral and substantially horizontal extension 12 which lies n over the work support 10 and has a slot 13 therein through which the needle and awl j shaft 9, as is clearly shown in Fig. 1 of the drawing.

The presser-root 11 is provided at as lower end with a handle 17 :and vat the juncture ofsaid handle with the 'shank 'of the presser-'foot with a laterallyc'lisposed pin 13 to which 'is"secured one end of a helical spring 19, 'the other end of 'which is secured to a pin20 on the standard't'at a'suitable-point thereon.y

Mounted'en tl'ie'driveshaft 7 to: tiirn therewith, is la di'sk 21 'which is @providedfin one of its faces'wi'thfacfam grove 22 for'cooperation with a `roller"23 -journaled on lan arm 24: extended from a link 25 `which `is pivotally connected fat 'its vupperend lto 'an arm '26 of Vthe standard Gand is similarly connectedjat its lowerend to 'a bar V'which is locate'dneartlie lower vportion "of the cam face of the disk 21afnd -entendsf'forwarclly andsubstantially horizontally near the side of the shank 11a of the p resser-'fobtadjfac'ent the standard '8 tand is "m'c'jvably "supported near itsl free endb'y a roller28'journaled on the lower portion of saidfs'liank. This bar is provided on 'its upper surface from its front end rearwardly: to asuitable distance with vtransverse serrations or teeth 29 to mesh 'withery engage "teeth `30"'o'nga jaw or block 31 'which is rigidly secured to that side of 'the upper portion Iolf the lever 32 'adjacent'thefinner "surface of the shank 11a of ythe presser-foot, on which surface of said shank the Vlever 32 is fulc'rumed by means of Va suitable pivot 33 extended through 'a suitable vopening in the VVFupper portion of the 'lever 32 `and through vthe opening 34 inthe block 31. The upper portion of the lever32 is extended Vforwardly and 'somewhat below the pivot 33 andhas o'n its'said 'lower portion 4a pin 35 which is laterally extended towards the standard 8 and isfor' co-action with the releasing trigger 'or member for the locking mechanism, as will be presently' explained.

The above mentioned trigger or member comprises an elbow-shaped piece 36 having its front end downwardly and rearwardly beveled as vat 37, seev Figs-f3 land. '5,r for'slidable yco-action with a pin 38 which' is eccentrically mounted on the'surface of the standand ,8 "adjacent the lever `32 at a point below and forward-1y of'thenpivot Yor fulcrum of said lever.

By mounting the pin 38 ecentri'cally on the standard 8, it is manifest that by turning it inthe proper direction, ,the bearing surface thereof for the beveled end 37 of the trigger 36 can be adjusted as desired. The trigger 36 is provided at its end opposite the beveled end 37 with a laterally eX- 'tended apertured boss 39 and said 'boss is provided at its lower portion with a lateral extension or foot 40 for co-operation with lthe bar '27,011 the surface of which adjacent the lever 32, said trigger is pivotally secured by means of "abolt l1 extended through the` aperture -of said boss and a suitable openingjin the bar 27 at a point therein re'arwardlyiof 'the yrear edge of the shank 11a ofv thepresser-foot.

y'On its side adjacent theshafnk illf'offthe presser-foot, the bar 27 `is yprovidedfwith '31a stop iniei'n'ber 42 for "co-:action 'with the rear edge or surface of said shank, and in the presei'it instance is shown inthe form "of-an elongated plate mounted lon 'the bolt il Vrand held'inplace by means l'of faiiut43'i'nthr'e`adedengagement withthe said bo1t,but-it'will,

be `'underiteod that any'other stopping `device `may be employed.

As is -clearly" shown in` Figs. 1 and '3, `the lockingV l'ever' 32 is 'extended' downwardly to about the'same extent asis thelo'wer'end of the presser-foot l11 and "said lever is equipped with a handle portion 144 `at its lo'werf'eX-tremity. A spiral spring 215 is -interposedibetween the handle portions "of the presser-foot 'and the portion 44 ofthe locking lever :for the 4purpose of zeX'eitiiig its tension vagainst 'the la'st named handle portion to "there-by cause the `jaw V31 and the upper portion ofthe locking lever vto 'be actuated downwardly and forwardly of its fulcr'um, which operation will automatically hold vthe'totlied jaw 31and the-:'pinfB o'n the lower l:front portion 'of the lever 32 in positionto 'engage vthe Ateeth29 of thebar 27 and the upper surface of the front' partof the trigger36,"e:cept whensaid 'trigger-is manipulated, by causing the parts lof'tlie mechanism yto assume'about the positions shown by dotted lines in'Fig. loffthe drawings.` l/Vhen in such'p'c`isitic` 'ns,I it is-manifest that'the extension 12`of'the presserfoot will be raised to a considerable distance above the work-support 10, thuspermitting the insertion, "adjustment `or withdrawal kof the work. 'When thezpartsare in 'thepositions' shown by continuous lines in Figxl, it'will be observed.l that the beveled-end37 'of the 'trigger will jbe-retracted rearwardly fromthe .pin 438 with which it co-acts as well'V as with the pin i35,to;throw thejawteeth out of 'engagement with .the teeth of the said bar, and to caus'e the trigger tomaintain the above mentionediposition untilthebaris reciprocated forwardly. The Arear end ofthe trigger or rather the lower portion of the lateral boss 39 thereon,

is provided with the lateral extension 4,0 to engage the lower edge of the bar as shown in Fig. 1 of the drawings. Y

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is:

l. In a sewing machine, the combination with a work-support, of a pivoted presserfoot co-operating therewith, a spring to actuate said foot in one direction, a locking lever fulcrumed on said foot and having a portion extended forwardly and below its fulcrum provided with a lateral jaw, cam controlled means including a reciprocatory bar (1o-operating directly with said jaw for locking the foot against pivotal movements, and means carried by said bar for engagement with a part of the front portion of said lever for releasing said locking means.

2. In a sewing machine, the combination with a work-support, of a spring-actuated pivoted presser-foot co-operating therewith,

a locking lever fulcrumed on said foot and having a portion extended forwardly and below its fulcrum provided with a lateral jaw having teeth on its lower extremity, cam controlled means including a reciprocatory bar having teeth for co-operation with the teeth of said jaw for locking the foot against pivotal movements, and means carried by said bar for engagement with a part lof the front portion of said lever for releasing said locking means. Y

3. In a sewingvmachine, the combination with a work-support, of a pivoted presserfoot co-operating therewith, a locking lever fulcrumed on said foot and having a portion extended forwardly and below its fulcrum provided with a lateral j aw having teeth on its lower extremity, cam controlled means including a reciprocatory bar having teeth for co-operation with the teeth of said jaw for locking the foot against pivotal movements, an upwardly and Jforwardly extended trigger pivotally mounted at its rear end on said bar rearwardly of the fulcrum of the locking lever having its front end downwardly and rearwardly beveled and adapted for engagement with a part on the front portion of said lever, and a fixed pin located in the path of the beveled end of said trigger whereby said locking means will be released.

4. In a sewing machine, the combination with a work-support, of a spring-actuated pivoted presser-foot co-operating therewith, a locking lever fulcrumed on said foot and having a portion extended forwardly and below its fulcrum provided with a lateral jaw having teeth on its lower extremity, a cam, a link pivoted at one end on a fixed pivot, a roller carried by said link and cooperating with said cam, a bar pivotally secured at its rear end to the lower portion of saidV link and having teeth on its-upper front portion for engagement with the teeth of said jaw, said bar being supported for reciprocatory movement, a trigger pivotally mounted at its rear end on said bar and having its opposite end downwardly and rearwardly beveled, a projection lixed in the path of the beveled end of said trigger, the upper portion of the front par-t of said trigger being downwardly and forwardly inclined and adapted for engagement with a part on the .front portion of said locking lever whereby in the forward movement of said bar the said locking means will be released.

5; In a sewing machine, the combination with a work-support, of a vertically disposed presser-foot co-operating therewith and havingl at its lower portion a handle, a spring to actuate said foot in one direction, a vertically disposed locking lever fulcrumed on said foot and having a portion extended forwardly and below its fulcrum provided with a lateral jaw having teeth on its lower extremity, said lever having at its lower portion a handle spaced from the handle of the presser-foot, a spring interposed between said handles, cam controlled means including a reciprocatory bar having teeth for cooperation with the teeth of said jaw for locking the foot against pivotal movements, an upwardly and forwardly extended trigger pivotally mounted at its rear end on said bar rearwardly of the fulcrum of the locking lever having its front end downwardly and rearwardly beveled and adapted for engagement with a part of the front portion of said lever, and a fixed pin located in the path of the beveled end of said trigger whereby said locking means will be released by the forward movement of said bar.

LEO J. DU MAIS. FLOYD E. MINER. 

